| Size SleeveX | Max. Bore d1 / d2 mm | Outer Dia D mm | Hub Outer D1 Dia mm | Total Length L mm | Sleeve Length L1 mm | Hub Length l1 / l2 mm | Space Betⁿ Hubs l3 mm | l4 | l5 | No. of Teeth | Extra Long Hub Length l1 / l2 mm |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M32 | 32 | 75 | 50 | 84 | 48 | 40 | 4 | 13 | 18 | 40 | 55 |
The M32 is a specialized mid-range coupling. It shares the same total length ($L$) and hub length ($l1$) as the M28, but increases the Outer Diameter (D) and Hub Outer Diameter (D1) to maintain structural integrity around the larger bore.
Extracted from the dimensional table for the M32 configuration:
| Specification | Metric Value |
| Max Bore Capacity (d1 / d2) | 32 mm |
| Outer Diameter (D) | 75 mm |
| Hub Outer Diameter (D1) | 50 mm |
| Total Length (L) | 84 mm |
| Sleeve Length (L1) | 48 mm |
| Standard Hub Length (l1 / l2) | 40 mm |
| No. of Teeth | 40 |
The M32 is optimized for balanced performance in medium-duty industrial drives:
High Resolution (40 Teeth): The jump to 40 teeth is significant. In elastomeric couplings, a higher tooth count generally translates to smoother torque transmission and a more "forgiving" engagement, which is critical for the larger motors that use 32 mm shafts.
Structural Beefing: To support the 32 mm bore, the Hub Outer Diameter (D1) has been expanded to 50 mm (up from 44 mm in the M28). This ensures the "wall thickness" of the hub remains strong enough to prevent cracking under high torsional stress.
Standardized Footprint: Because it shares the 84 mm total length with the M28 and M38, engineers can often swap these models within the same machinery footprint if motor sizes are upgraded.
Extra Long Hub Option: Like the M28, it supports an Extra Long Hub of 55 mm for applications requiring maximum shaft contact.
| Feature | M28 | M32 | Change |
| Max Bore | 28 mm | 32 mm | +14% |
| Outer Dia (D) | 65 mm | 75 mm | +10 mm |
| Teeth Count | 34 | 40 | +6 Teeth |
| Total Length (L) | 84 mm | 84 mm | No Change |
Standard Electric Motors: Fits many 5.5 kW to 7.5 kW motors (depending on frame size).
Industrial Blowers: The 40-tooth count is excellent for high-speed air-moving equipment where vibration must be kept to a minimum.
Process Pumps: Used in chemical and water treatment where a 32 mm shaft is a common standard.
Summary
The M32 provides a higher torque-handling capacity than the M28 without taking up any additional axial space. With 40 teeth and a 75 mm outer diameter, it is a robust choice for 32 mm shafting.
